The present invention relates generally to MLC (multilayer ceramic) frequency selective circuit structures. More particularly, the subject invention pertains to MLC frequency selective circuit structures having a solenoid and toroid coil geometry in a multilayer electronic package which functions as a frequency selective tuned circuit in which both the number of turns and the aspect ratio of the solenoid coil are selected to adjust the tuned frequency. In some embodiments, a plurality of such coils can be connected together to provide a selected bandwidth about a tuned center frequency.
The prior art has generally provided a tuned circuit by mounting inductors and capacitors on a semiconductor MMIC (monolithic microwave integrated circuit), on a package, or on a PCB (printed circuit board).
The present invention provides a solenoid and toroid coil geometry in a multilayer electronic package which functions as a frequency selective tuned circuit. Both the number of turns and the aspect ratio of the solenoid coils can be selected to adjust the tuned frequency. In some embodiments, a plurality of such coils can be connected together to provide a selected bandwidth about a tuned center frequency.
The frequency selective tuned circuits of the present invention can be extended to semiconductor MMICs (monolithic microwave integrated circuits), PCBs (printed circuit boards), and other packaging configurations.
The present invention provides MLC frequency selective structures that take advantage of MLC characteristics. An MLC frequency selective circuit is a structure that can be integrated into an MLC package using conventional MLC manufacturing techniques and that combines an inductive effect and a capacitive effect as an integrated entity which functions as a frequency dependent circuit. The dimensions of the structure can be selected to determine a) capacitance and inductance, b) the tuned frequency at which resonance occurs, c) the bandwidth, and d) the energy storage capability (Q) at that frequency. The toroidal and wide-link solenoidal geometries of the present invention have inherently much higher Qs than many other structures. Also more than one such coil can be connected together to further adjust parameters such as the bandwidth about the selected tuned frequency. Such circuits can also form part of a larger circuit including active devices and other passive devices to provide electrical functions such as amplification, oscillation, filtering, impedance matching, etc.